The purpose of this planning grant is to establish a database to identify patients eligible to participate in a prospective study of risk factors for diabetes incidence in Blacks, Hispanics, and non-Hispanic Whites with hypertension. The database will contain demographic and clinical information on patients with hypertension, diabetes, and impaired glucose tolerance who receive ongoing primary care in a network of publicly supported community health centers in Houston, Texas. The racial/ethnic distribution of the adult patients in this system is approximately 42% Black, 36% Hispanic, and 19% non-Hispanic White. Considerable data have been collected on the 6,500 diabetic patients under care in the system, but the number and characteristics of patients with hypertension or impaired glucose tolerance are not known. Diabetes is more common in Blacks and Hispanics than in non-Hispanic Whites, and hypertension is more common in Blacks. Recently, evidence has suggested that these two conditions share a common etiologic link. The proposed study of factors that predict incidence of diabetes in a multi-ethnic cohort of hypertensives could lead to a better understanding of the relationship between the two conditions and provide information to guide the design of effective treatment and primary prevention strategies. The database established during this project will also serve as a resource to other investigators in the Texas Medical Center (Houston, Texas) interested in conducting clinical, behavioral or epidemiologic research on diabetes and hypertension in minorities.